Between zinc and a hard place

Posted by ouroboros under OxidationComments Off on Between zinc and a hard place

Following up on the zinc homeostasis story, which we discussed here earlier in the week (Think zinc), I wanted to draw your attention to Larbi et al.‘s review of the relationship between age-related zinc deficiency, heat shock protein expression, and immunological aging:

… We believe that chronic stimulation of T-cells enhances the appearance of apoptosis-resistant anergic dysfunctional cells; in humans in vivo these are predominantly specific for antigens of persistent viruses, especially CMV. Concomitantly, age-associated zinc deficiency is common and one hypothesis is that lack of zinc bioavailability contributes to impaired T-cell function. This could further compromise the integrity of T-cells under chronic antigenic stress, which can be modelled in long-term clonal cultures in vitro. Newly synthesized heat-shock proteins (HSPs) protect the cellular proteins from degradation under such conditions. In this short review we will briefly outline the role of heat-shock proteins and zinc deficiency in aging in order to finally discuss our own results in the context of a link between HSPs, aging and zinc.

Taking this argument together with the idea that decreasing Zn2+ levels are a compensatory mechanism to avoid oxidative stress, we see another example of a common theme in the biology of aging: Cells are being pulled in opposite directions along a given axis (in this case, [Zn2+]i), trying to find an optimum between two bad outcomes (in this case, immune dysfunction on the one hand, and high levels of oxidative damage on the other).